Strategies and Structures for Improving Data Use - An SEA Perspective

Presentation to the SDP Summer Institute for Leadership in Analytics August 6th-8th 2012

Jared Knowles, Policy Research Advisor at Wisconsin Department of Public Instruction

The Big Questions

Meet the Inference Tree

plot of chunk treedata

What is an inference tree?

How can it be used?

The R Code

library(partykit)
mypar <- ctree_control(testtype = "Bonferroni", mincriterion = 0.99)
mytree <- ctree(mathSS ~ race + econ + ell + disab + sch_fay + dist_fay + attday + 
    readSS, data = subset(df, grade == 3))
plot(mytree)

Using Graphics To Tell a Story: Maps

Using Graphics to Tell a Story: Animations

R Code

# Draw subset
library(ggplot2)
for (i in 1:100) {
    mysub <- subset(studata, math_percentile == i)
    png(file = "frame", i, ".png", width = 1000, height = 750)
    qplot(grade, mathSS, data = mysub, geom = "lines", group = stuid, alpha = I(0.2)) + 
        prof_poly() + stat_summary(median, data = mysub, color = "gold", size = I(1.04)) + 
        geom_text(Labels)
    dev.off()
}

Demonstrate Distributions Linking Tests

This is different than research

Ask Jen

The Problem?

Policy Relevant Research is the Answer

John Tukey said:

An approximate answer to the right problem is worth a good deal more than the exact answer to an approximate problem

Fast

Focused

Approximate

Policy relevant research is everywhere

Getting Value from Data

How to do this?

My Favorite

Wisconsin’s Solution

R

R is

But wait…

Isn’t R?

Confusing?

Buggy?

How does Wisconsin use R?

How else is Wisconsin using R?

Some Caveats

Thoughts

  1. What are some ways inference trees could be used in your agency?
  2. What types of analyses would be useful across district and state agencies?
  3. Sharing work with common data is something we all have an interest in to understand our work. How can we make this happen?

Attribution and License

Public Domain Mark
This work (Data Analysis in an SEA, by Jared E. Knowles), in service of the Wisconsin Department of Public Instruction, is free of known copyright restrictions.